In debian sid (amd64)
You can solve it installing libaccess-bridge-java-jni
Maybe can be a 'required' by josm.
This package install libjava-access-bridge-jni.so
to /usr/lib/jni/libjava-access-bridge-jni.so, so you need to create a
symlink
in /usr/lib/jvm/java-6-openjdk/jre/lib/ext/libjava-access-bridge-jni.so
ln
-s /usr/lib/jni/libjava-access-bridge-jni.so /usr/lib/jvm/java-6-openjdk/jre/lib/ext/libjava-access-bridge-jni.so